Machine for making envelopes with moistenable or self-sealing closure flaps

ABSTRACT

Envelopes or flat bags are made with closure flaps which are either gummed with dextrin or a similar substance which becomes adhesive when moistened, or the flaps and their corresponding contact areas of the rear side are both gummed with latex or similar adhesive which sticks in the dry state. These gumming operations are carried out in a single pass through a machine which includes an envelope-folding machine which may have stations for printing and embossing the envelopes or bags and making windows or sticking linings therein and which forms a single structural unit with the following consecutively arranged stations: (a) a station composed preferably of suction discs for receiving individually from the folding machine finished folded envelopes or bags with ungummed closure flaps; (b) a station for reopening the envelopes or bags; (c) a station for applying either dextrin or the like to the closure flap, or applying latex or the like to the closure flap and the corresponding contact area upon the rear side of the envelope or bag, at a distance from the edges thereof; (d) a station for staggering the envelopes or bags to which adhesive has been applied; (e) a station for drying the staggered envelopes or bags; and (f) a station for collecting finished envelopes or flat bags either with closure flaps open or with folded flaps, preferably standing on edge upon a delivery table.

United States Patent [72] Inventors Richard Winkle! Burgermeister-Win k-Strase, 5455, Rengsdorf; Kurt Dunnebier. am Burltenlitang 5451, Gladbach, both of, Gey [21] Appl. No. 821.293 [22] Filed May 2. 1969 [45] Patented Sept. 14. I971 [32] Priority Dec. 28. 1968 [33] Germany [31] P18172973 [54] MACHINE FOR MAKING ENVIEL1PES WllTll-ll MOISTENABLE 0R SELF-SEALING CLQDSURE FLAPS 2 Claims, 8 Drawing Figs.

{52] U.S. Cl 93/74, 93/58 ST, 93/62 [51] Int. Cl... ..lB3llb 211/02, B31b 21/26, 33151762 [50] Field of Search 93/61-75, 53 OR, 58 ST [56] References Cited UNITED STATES PATENTS 370.969 10/1887 Rheutan 93/74 1.121.125 12/1914 Novick.. 93/74X 2,197,828 4/1940 Novick 93/61 2.244.723 6/1941 Novick 93/61 B 2,348,864 5/1944 Staude 93/74 X 2.604.829 7/1952 Heywood 93/74 Primary ExaminerWayne A. Morse, Jr. AnomeyRichards & Geier ABSTRACT: Envelopes or flat bags are made with closure flaps which are either gummed with dextrin or a similar substance which becomes adhesive when moistened, or the flaps and their corresponding contact areas of the rear side are both gummed with latex or similar adhesive which sticks in the dry state. These gumming operations are carried out in a single pass through a machine which includes an envelope-folding machine which may have stations for printing and embossing the envelopes or bags and making windows or sticking linings therein and which forms a single structural unit with the following consecutively arranged stations: (a) a station composed preferably of suction discs for receiving individually from the folding machine finished folded envelopes or bags with ungummed closure flaps; (b) a station for reopening the envelopes or bags; (0) a station for applying either dextrin or the like to the closure flap, or applying latex or the like to the closure flap and the corresponding contact area upon the rear side of the envelope or bag, at a distance from the edges thereof; (d) a station for staggering the envelopes or bags to which adhesive has been applied; (e) a station for drying the staggered envelopes or bags; and (f) a station for collecting finished envelopes or flat bags either with closure flaps open or with folded flaps, preferably standing on edge upon a delivery table.

PATENTEDSEPMISTI 3,604,318

SHEET 1 OF 5 Inventors R. Wink/er A Dunneb c'er ma-144t- ATTQ (LN E55 PATENTEDSEPMma 3,604,318

SHEET 2 OF 5 Inventor: R. Min/dam K. Db'nnebier dhawb -g a ATTomuflss PATENIEU SEP 1 4 I97i SHEET 0F 5 Inventors R. Win/(bar @A K. Dfinnebier MACHINE FOR MAKING ENVELOPES WITH MOISTENABLE OR SELF-SEALING CLOSURE FLAPS This invention relates to a machine for manufacturing envelopes or flat bags, referred to hereinafter as envelopes, either with closure flaps gummed with dextrin or the like which becomes adhesive when moistened, or with selfsealing gumming of latex or some other similar adhesive which sticks when dry, hereinafter referred to as latex, in one single pass through the machine, the construction of the resulting selfsealing envelopes being such that they can be filled by an automatic envelope-filling machine.

Prior art self-sealing envelopes have a straight, wide and short closure flap as a rule. A strip of latex which usually extends as far as the edges of the envelope is applied to the closure flap and also to the corresponding place on its rear side. The closure flap and the latex-coated portion of the rear side of envelopes of this kind are as a rule both folded over against the rear side, so that the latex strips are covered for storage purposes.

Machines for manufacturing self-sealing envelopes of this type are known in prior art. It is also known to use a separate gumming machine which draws envelopes with ungummed closure flaps from a stack to apply and dry a strip of latex on their closure flaps and rear sides, the envelopes being as a rule guided in the longitudinal direction of the latex strips past latex-applying discs which apply the latex as far as the lateral edges of the envelopes.

Self-sealing envelopes manufactured in this manner are unsuitable to be filled mechanically by means of automatic envelope-filling machines, since the latex is applied up to the edges of the envelopes, so that there is the risk that they will get stuck to one another, and also because their closure flaps and the latex-coated portions of their rear sides are folded OVfil'.

Self-sealing envelopes for mechanical filling must have closure flaps standing open, and no folded-over latex strips on their rear sides, and the latex strips must not extend as far as the edges of the envelopes or their closure flaps, since if the envelopes stick to one another, the automatic filling machine may break down.

There is a growing demand for self-sealing envelopes suitable to be filled by means of automatic filling machines. However, suitable self-sealing envelopes cannot be produced by the majority of conventional machines for manufacturing envelopes having moistenable closure flaps. These machines can merely produce envelopes with ungummed closure flaps, the latex strips being applied by a separate gumming machine. The envelope-making machine therefore operates uneconomically, since it is not used to the fullest extent. Additional labor is required for the separate gumming machine for applying latex strips to the closure flaps and the corresponding places on the rear sides of the envelopes, which are folded with ungummed closure flaps. Moreover, the envelope-making machine must be able to deliver envelopes with their closure flaps standing open, or else the gumming machine must be able to open the closure flaps, and as a rule neither takes place. In general it is uneconomical to manufacture self-sealing envelopes by two separate machines.

An object of the present invention is to eliminate these drawbacks of prior art machines.

Another object is the provision of a single machine which combines the envelope making operation with those of gumming and properly arranging the envelope flaps.

Other objects of the present invention will become apparent in the course of the following specification.

The machine of the present invention is so constructed that it is capable of manufacturing both types of envelopes or flat bags, namely, those wherein the closure flaps are gummed with dextrin or the like which becomes adhesive when moistened, as well as those wherein the closure flaps and the corresponding contact areas of the rear side are gummed with latex or similar adhesive which sticks in the dry state. These operations are carried out in a single pass through the machine. The machine of the present invention combines an envelope-folding machine which can have stations for printing and embossing the envelopes, making windows or sticking linings therein, with the following consecutively arranged stations connected to the envelope-folding machine to form one structural unit:

a. a station, consisting preferably of suction discs or the like, receiving individually from the folding machine finished folded envelopes or flat bags with ungummed closure flaps;

b. a station for reopening the individual envelopes or flat bags;

c. a station for applying either dextrin or the like to the closure flap, or latex or the like to the closure flap and to the corresponding place of contact on the rear side of the individual envelopes or flat bags, at a distance from the edges thereof;

d. a station for staggering or overlapping the envelopes or flat bags to which the adhesive has been applied;

e. a station for drying the overlapped envelopes or flat bags,

and

f. a station for collecting the finished envelopes or flat bags either with the closure flap standing open or with the closure flap folded over against the rear side of the envelopes or flat bags, preferably standing on edge on a delivery table.

The machine according to the invention can manufacture equally economically either finished folded envelopes or fiat bags with moistenable closure flaps, or self-sealing envelopes or flat bags with open closure flaps suitable for filling on automatic envelope-filling machines. Envelopes or flat bags having moistenable closure flaps may be delivered with their closure flaps standing open. Other economic advantages of the machine according to the invention are its all-purposes versatility, and the elimination of extra labor required for a separate gumming machine. Another advantage is that the closure flaps of the envelopes or flat bags manufactured according to the invention are first folded over and then opened again for gumming, so that when the envelopes or flat bags are closed after being automatically filled, they can be folded over much more reliably exactly along the folding line of the closure flap than if this line had been merely faintly indicated.

Preferably, the station (e) for drying the overlapped envelopes is so constructed in the form of belts extending partly under or also over the folding machine, that the following station (f) for collecting the finished envelopes has a position adjacent the feed end which is advantageous for operating the machine.

According to a different embodiment of the present invention, the machine constitutes a unit for the optional manufacture of self-sealing envelopes which can be connected to an existing machine for manufacturing envelopes with moistenable closure flaps, instead of being combined with a special folding machine which does not have devices for staggering blanks and for gumming and drying the closure flaps. Such a machine unit also has economic advantages over the use of a separate gumming machine for the application of latex, since it eliminates labor required for the gumming machine.

The invention will appear more clearly from the following detailed description when taken in connection with the accompanying drawings, showing by way of example only, preferred embodiments of the inventive idea.

In the drawings:

FIG. 1 is a diagrammatic side view illustrating a portion of a machine according to the present invention.

FIG. 2 is a continuation of FIG. 1 and shows the portion of the same machine located to the left of FIG. 1.

FIG. 3 is a continuation of FIG. 1 and shows the portion of the same machine located to the right of FIG. 1.

FlGS. 4 and 5 are partial diagrammatic views illustrating a machine of the present invention combined with an existing envelope-making machine; FIG. being the left-hand extension of FIG. 4.

HO. 6 is a diagrammatic side view illustrating, on a larger scale, a portion of the machine shown in FIG. 1, namely, the stations which follow the folding machine up to the adhesiveapplying station.

FIG. 7 is a side view of a self-sealing envelope suitable for filling on an automatic filling machine.

FIG. 8 is a side view of a prior art self-sealing envelope which can not be filled on an automatic filling machine.

The machine of the present invention shown diagrammatically in FIGS. 1-3, includes a folding machine 1 which can be of any suitable type and which is not shown in detail. It includes an intake station 2 provided with a stack 3 of blanks cut to size, printing mechanisms 4, a gumming and folding station 5 for the side and bottom flaps of the envelopes, a folding station 6 for the ungummed closure flaps and a suction roller 7. The suction roller 7 which rotates in the direction of the arrow, seizes the finished folded envelopes individually closely behind their front edges with their closure flaps on the outside, and conveys the envelopes onwards. The roller 7 is followed by the following elements rotating at the peripheral speed of the suction roller 7 of the folding machine, in the direction indicated by the arrows: suction discs 8, a suction roller 9, segments 10 with machining rollers 11 and discs 12 with matching rollers 13. These are followed by discs 14, rotating at a lower peripheral speed, with matching rollers 15 for reducing the conveying speed of the envelopes, and rollers 16 with matching rollers 17. These are followed by a suction roller 18 located opposite an adhesive-applying roller 19 which bears gumming sections adapted to the shape of the strip of adhesive to be applied, for example, in the case of latex, two gumming sections 20, 21, but for moistenable adhesives only one gumming section 21. The adhesive is supplied to the gumming sections from a trough 22 through rollers 23, 24. Guides 39 are provided to guide the envelopes over the rectilinear path from the segments 10 to the suction roller 18.

A portion of the machine, according to the invention, which adjoins the folding machine is shown in greater detail in FIG. 6. The suction roller 9 is provided with several rows 26, 27 of suction holes. The row 26 of suction holes is so connected periodically through an arcuate control slot 30 to a suction air line, that it seizes an envelope arriving on the suction discs 8 close behind the folding edge of its closure flap and entrains the envelope as far as below the arcuate guide 31, where it releases the envelope a short distance in front of an adjustable stop 32, so that the envelope 33 runs freely against the stop 32 and is aligned thereby. The rear end 34 of the envelope sticking out of the suction roller 9 is then disposed in the apertures of the segments 10. On further rotation of the segments 10, their edge 36, which is somewhat withdrawn from the outer diameter of the segments, entrains the rear end 34 of the envelope to the extent of about 3 mm. beyond the line connecting the centers of the segments 10 and the matching rollers 11. The stop 32 is adjusted accordingly. When the segments 10 continue to rotate, and the "seizing edge 37 seizes the envelope, it is entrained between the segments 10 and the matching rollers 1 l, in the opposite direction from its. previous direction of conveyance.

Associated with the matching rollers 11 is a fixed flap opener 38 which hooks below the closure flap of each envelope pulled away from the stop 32 through the segments 10 and their matching rollers 11, the closure flap flapping open, due to the bending of the envelope around the suction roller 9, to the extent allowed by the distance between the guides 31 and the suction roller 9. The envelopes are therefore fed, with their closure flaps open, between the roller 12- and its matching rollers 13 to a roller 14 rotating at the same r.p.m. as the matching rollers 15.

Due to the smaller diameter of the roller 14 as compared to that of the roller 12, the speed of the envelope is reduced, the envelope being fed between rollers 16 and their matching rollers 17 to a suction roller 18 which preferably has twice the diameter of the roller 14. The suction roller 18 is provided with two opposed groups of rows 28, 28' of suction holes by means of which the suction roller 18 alternately seizes an envelope and sucks it, including its closure flap, tightly against its generated surface, while the gumming sections 20, 21 of the adhesive-applying roller 19 apply a strip of latex 20', 21' to the rear side and to the closure flap of the envelope in the case of self-sealing envelopes, or else one single gunning section 21 applies a strip of dextrin or the like solely to the closure flap of moistenable envelopes. As shown in FIG. 7, the gumming sections 20, 21 apply the latex strips 20', 21 at a certain distance a from the edges of the envelope.

FIG. 8 shows by comparison a prior art latex application extending as far as the edges of the envelope, as disclosed, for example, in U.S. Pat. No. 2,730,989.

The suction roller 18 is followed by a roller 41, having matching rollers 42, adjoined by belts 44, stretched over rollers 43, and having pressure rollers (FlG. 1). A guide 39' for the envelopes is provided between the rollers 18 and 41. The freshly gummed envelopes are seized at their adhesivefree lateral edges between the roller 41 and its matching rollers 42, and between the belts 44 and the pressure rollers 45, and are conveyed onward at unchanged speed.

The belts 44 and pressure rollers 45 are followed by upper belts 47 running over a roller 46 and by staggering rollers 48, the latter being followed by upper belts running over a roller 49 (FIG. 2). The belts 47, 50 and the staggering rollers 48 move at a speed which is so low that the individually arriving envelopes are pushed under one another in such a way that only their adhesive coated portions lie exposed upwardly between the top belts 50. The belts 47 bearing the overlapped envelopes are guided over a plurality of rollers 51 and an end roller 52, the inner run of the belts 47 being guided over a number of rollers 53 and a drive roller 54 whose speed can be adjusted in accordance with the required staggering width. The belts 50 are stretched over a number of rollers 55 and an end roller 56 and are entrained by the belts 47 by friction. The inner run of the belts 50, due to the arcuate guiding of the belts, presses the overlapped envelopes firmly against the belts 47 by their adhesive-free edges. An air channel 40 is located between the belts 50 from which hot air flows out onto the envelopes to dry the gumming.

The belts 47, 50 are followed by conveying chains 58 or the like which are stretched over wheels 59 and convey the envelopes, still overlapped under the folding machine 1 in the direction indicated by the arrows (FIG. 1). Then follow inner belts (FIG. 3), stretched in an arc around a drum 62 and rollers 63, 64, and also outer belts 70, which are stretched over rollers 67-69, which press against the inner belts 65, and which guide the envelopes still overlapped upwards in the direction indicated by the arrows and transfer them to following separating elements 71, 72 which rotate at increased peripheral speed and separate the envelopes from their overlapped position.

Then there follows a folding station having a suction roller 75, rollers 73, 74 and a folding pocket 76, a suction roller 77, depositing discs 78 formed with slots 79 and a depositing table 80. 1f the envelopes are to be collected on the delivery table with their closure flaps folded against their rear sides, as is usually the case with moistenable envelopes, each envelope is pushed into the folding pocket individually between the rollers 73, 75 as far as a stop (not shown), pulled backwards out of the folding pocket again between the rollers 74, 75, while at the same time its closure flap is folded over, whereupon each envelope is seized by the suction roller 77 and pushed into a slot 79 in the depositing disc 78, which deposits the envelope standing on edge in a stack 82 retained by a stop 81 on the delivery table 80. Belts (not shown) running slowly over the surface of the delivery table 80 can be provided below the stop 81 and the stack 82 in a manner known per se, the belts moving the stop 81 and the stack 82 away from the depositing discs 78 in accordance with the space required by the arriving envelopes.

If the envelopes are to be stacked on the depositing table with their closure flaps standing open, the envelopes are transferred through the suction roller 75, past the folding pocket, to the suction roller 77, and they move into the stack 82, as described, with their closure flaps open and at the top.

In the second embodiment of the invention, illustrated in FIGS. 4 and 5, a known, complete envelope-making machine for the manufacture of envelopes with moistenable closure flaps, and if necessary inscriptions and windows, takes the place of a simple folding machine without the devices for gumming the envelope closure flaps. The main components of the machine, which is merely illustrated diagrammatically, are a feeding device 101 associated with a stack 102 of blanks, printing mechanisms 103, a station 104 for making windows in the blanks, a station 105 for staggering the blanks, a station 106 for gumming the closure flaps, a drying track 107 extending along and below the machine, and a folding machine 108 (shown only in part) having a folding station 109 for the moistenable closure flaps of the envelopes. Following the folding station 109 is a suction roller 110 (identical with the suction roller 7 shown in FIG. 1), suction discs 111 (identical with the suction discs 8 shown in FIG. 1), depositing discs 112 provided with slots 113, and a delivery table 114. That part of the machine which is located between the suction roller 9 and the belts 47, 50, above the suction discs 111 and depositing discs 112 is precisely identical with the first embodiment of the invention, so that in this part of FIGS. 4 and 5 like members have the same reference numerals as those of members shown in FIGS. 1 and 6.

As shown in FIG. 5, in this embodiment the belts 47 run over two superimposed end rollers 117, 118, and the belts 50 run over an end roller 119. Spring loaded rollers 120, 121 press against the part of the belts 47 which runs downwardly between the rollers 117, 118. A delivery table 122 is disposed below the end roller 118.

The machine shown in FIGS, 4 and 5 operates as follows:

Envelopes with folded moistenable closure flaps produced by the envelope-making machine 101-111 are transferred by the suction discs 111 to the suction roller 9, which pushes the envelopes individually into slots 113 in the depositing discs 112. For this purpose, the suction roller 9 is formed with both the control slot 30 and a shorter control slot 30 for controlling the series 27 of suction holes (FIG. 6). The depositing discs 112 deposit the finished envelopes standing on edge in the form of a stack 115 with a stop 116 on the delivery table 1 14 (F IG. 4).

If the machine is to manufacture self-sealing envelopes with closure flaps standing open, the envelopes arriving with folded ungummed closure flaps from the folding station 109 are not transferred by the suction roller 9 to the depositing discs 112, but are entrained further as far as the stop 32 (FIG. 6). In the same manner as described in the first embodiment of the invention, the closure flap is then opened, the latex is applied, and the envelopes are staggered and dried between the belts 47, 50. At the end of the top belts 50, the staggered envelopes pass under pressing rollers 120, 121 and are collected standing on edge with their closure flaps open in the form of a stack 123 with a stop 124 on a delivery table .122 (FIG. 5). The distance between the bottom pressing rollers 121 and the delivery table 122 can be adjusted in accordance with the height of the self-sealing envelopes with open closure flaps. Slowly running conveyor belts for the stack can be provided on both delivery tables 114 and 122, as already mentioned in connection with the depositing table of the first embodiment.

If the machine is to manufacture envelopes with moistenable closure flaps standing open, the envelopes arriving finished and folded with gummed closure flaps from the envelopemaking machine 104-111 can be reopened in the same manner as for the production of self-adhesive envelopes. In this case there is no application of adhesive and no drying. The envelopes are collected with their closure flaps standing open on the delivery table 122,

We claim:

1. For use with an envelope-folding machine which may have stations for printing and embossing the envelopes and making windows or sticking linings therein, or with a machine for making finished and folded envelopes having flaps which may be gummed with a moistenable adhesive, a machine for manufacturing envelopes and the like with flaps provided with a moistenable adhesive or with flaps and corresponding rear contact areas provided with a self-adhering adhesive, in a single pass, through the machine which consists of a single structural unit, comprising in combination with an envelope folding means:

a. a station receiving individually the folded envelopes and having suction discs for conveying the envelopes,

b. a station reopening the envelopes individually,

c, a station applying a moistenable adhesive to closure flaps of individual envelopes, or applying a self-adhering adhe sive to closure flaps and corresponding rear contact areas of individual envelopes, at a distance from the edges thereof,

d. a station for staggering the adhesive-carrying envelopes,

e. a station drying the staggered envelopes, and

f. a station collecting the dried envelopes with the closure flaps standing open or with the closure flaps folded against the rear sides of the envelope, and comprising a delivery table, and means for delivering the envelopes standing on edge onto said delivery table.

2. A machine in accordance with claim 1, wherein the station collecting the dried envelopes comprises a folding pocket for folding the closure flaps of envelopes and a suction roller for keeping the closure flaps open. 

1. For use with an envelope-folding machine which may have stations for printing and embossing the envelopes and making windows or sticking linings therein, or with a machine for making finished and folded envelopes having flaps which may be gummed with a moistenable adhesive, a machine for manufacturing envelopes and the like with flaps provided with a moistenable adhesive or with flaps and corresponding rear contact areas provided with a self-adhering adhesive, in a single pass, through the machine which consists of a single structural unit, comprising in combination with an envelope folding means: a. a station receiving individually the folded envelopes and having suction discs for conveying the envelopes, b. a station reopening the envelopes individually, c. a station applying a moistenable adhesive to closure flaps of individual envelopes, or applying a self-adhering adhesive to closure flaps and corresponding rear contact areas of individual envelopes, at a distance from the edges thereof, d. a station for staggering the adhesive-carrying envelopes, e. a station drying the staggered envelopes, and f. a station collecting the dried envelopes with the closure flaps standing open or with the closure flaps folded against the rear sides of the envelope, and comprising a delivery table, and means for delivering the envelopes standing on edge onto said delivery table.
 2. A machine in accordance with claim 1, wherein the station collecting the dried envelopes comprises a folding pocket for folding the closure flaps of envelopes and a suction roller for keeping the closure flaps open. 